Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Accounts and other receivables, allowance for doubtful accounts and sales returns	$ 3,076	$ 3,746
Common stock, no par value
Common stock, shares issued	32,779,606	32,682,162
Common stock, shares outstanding	32,779,606	32,682,162
Common Stock, Shares Held in Employee Trust, Shares	68,268	67,726